a sphere and a cube have equal surface areas show

Question

A sphere and a cube have equal surface areas. Show that the ratio of the volume of the sphere to that of the cube is √6 : √π.

Ans:    S.A. of sphere = S.A of cube

   4π r² = 6a²

   r =    √6a²/4Π

∴ ratio of their volume v1/v 2  = 4/3πy³/a³

On simplifying & substituting, we get √6 : √π